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<div>Hi everybody,</div>
<div> </div>
<div>I have an understanding question regarding the utilization distribution in adehabitatHR.</div>
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<div>In general, the UD describes a probability density function which properties are that the values of the UD are nonnegative and the area under the curve equals to1.</div>
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<div>When I sum up the values of the UD within the adehabitatHR package I don't receive 1, only when I use the product of the values.</div>
<div>In the BBMM package the sum of the UD values is 1.</div>
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<div>Can anybody please help me to understand why the product of the UD values is 1 and not the sum?</div>
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<div>I provide here also an example code:</div>
<div>#adehabitatHR</div>
<div>library(adehabitatHR)</div>
<div>data(puechcirc)</div>
<div>x<-puechcirc[1]</div>
<div>bbmm<-kernelbb(x, sig1=6.23, sig2=58, grid=50)</div>
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<div> sum(bbmm$ud)<br/>
[1] 0.0001668006</div>
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<div>prod(bbmm$ud[-which(bbmm$ud==0)])</div>
<div>[1] 1</div>
<div> </div>
<div>#BBMM</div>
<div>library(BBMM)</div>
<div>BBMM <- brownian.bridge(x=locations$x, y=locations$y, time.lag=locations$time.lag[-1], location.error=20, cell.size=50)</div>
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<div>sum(BBMM[[4]])<br/>
[1] 1</div>
<div> </div>
</div>
<div>Thank you.</div>
<div>Best,</div>
<div>Ena Kenev</div>
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